CERN LHC

What is CERN?

CERN (Conseil Européen pour la Recherche Nucléaire) is the world’s foremost organisation for research into high-energy physics (HEP), a field whose aim is to discover the most fundamental secrets of matter.

CERN is based in Switzerland and funded by 20 European Member States (Austria, Belgium, Bulgaria, the Czech Republic, Denmark, Finland, France, Germany, Greece, Hungary, Italy, The Netherlands, Norway, Poland, Portugal, the Slovak Republic, Spain, Sweden, Switzerland and the United Kingdom). However, today CERN is a world-wide enterprise involving many other states with scientists and engineers of many nationalities. It is an important example of international collaboration: the nature of the experiments conducted at CERN is such that no single state could afford to fund them on this scale.

CERN’s networking needs

The World-Wide-Web was developed at CERN because of the needs of scientists to share data for analysis and interpretation. Today, the international networking needs of CERN are met by GÉANT2, the pan-European research network, and its NREN partners.

CERN’s most ambitious project to date, the Large Hadron Collider (LHC), is currently under construction. This facility, able to smash fundamental particles together at unprecedented energies, is said to be the largest scientific endeavour in history. It will produce data about the collisions, and the exotic and short-lived particles they create, at a rate of 15 Petabytes (15 million Gigabytes) per annum. It would be impossible to process all of this data at CERN, so it must be distributed to computing sites around the globe for analysis. GÉANT2 and the connected NRENs are tasked with meeting this challenge.

How the LHC will be connected

The structure of the LHC Computing Grid (LCG) is to distribute the data first to 12 Tier 1 sites, each connected to Tier 0 (CERN) by a dedicated wavelength switched path of 10Gbps. These paths are provided by the new hybrid (IP routed/ wavelength switched) structure of GÉANT2. Corresponding dark-fibre lightpaths will be provided by each of the European NRENs involved.

Each Tier 1 processing site will support a number of secondary Tier2 sites, usually within the same country. Connectivity between Tier1 and Tier2 sites will be provided by the relevant NREN. DANTE and these NREN partners (GARR, UKERNA, SURFnet, DFN, RENATER, REDIRIS, NORDUNET, ESNET and ASNet) are currently engaging with the HEP community to establish the necessary infrastructure. This page provides links to relevant documents and meetings on this topic.